1. Technical Field
The present disclosure relates to a monitoring system and a monitoring method which monitor an imaging area of a camera device in which, for example, a pilotless flying object flies.
2. Description of the Related Art
A flying object monitoring apparatus depicted in Japanese Patent Unexamined Publication No. 2006-168421 is capable of detecting the presence of an object and the flight direction of the object using a plurality of audio detectors which detect sounds generated in a monitoring area on a per-direction basis. If a processor of the flying object monitoring apparatus detects the flight and the flight direction of a flying object through audio detection using microphones, the processor causes a monitoring camera to face the direction in which the flying object flies. Furthermore, the processor displays a video which is captured by the monitoring camera on a display device.
However, when a pilotless flying object such as a drone is detected, if audio detection is performed by setting all directions in the monitoring area as a monitoring target, from the perspective of a non-directional microphone, a direction in which a frequency of a loud sound being generated is high cannot be set as a masking area. Therefore, in a case where a loud sound is detected in the monitoring area, an object in a direction of the masking area, which is different from a pilotless flying object originally desired to be detected, may be erroneously detected as a target pilotless flying object. In addition, if a masking area that is excluded from being a target is set in advance instead of setting all directions in the monitoring area as a monitoring target, it can be expected that detection of the pilotless flying object originally desired to be detected will be performed faster.
In a monitoring camera which changes an imaging direction in order to perform imaging by focusing on the detected flying object, it is difficult to visually present, to a user, the location in the imaging area of the camera device where the pilotless flying object is detected, and what kinds of sound source are present at which locations in the same imaging area.
In addition, in a case where a sound pressure in a frequency unique to the flying object such as a helicopter or a Cessna is greater than or equal to a predetermined set level, if the flying object is determined to be the monitoring target, when any sound is detected in the imaging area of the camera device, it is difficult to specifically present the volume of the sound as detailed visual information for sound, regardless of the magnitude of the volume of the detected sound at a sound source position.